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Modern mechanical EM transmitters, like radio towers and radar guns, rely on finely tuned mechanical structures. If these structures do not have the right shapes, the device fails to function.

Organic growth focuses on balances and on-the-fly tuning. It has to grow from infant to adult sizes. Organics tend to adapt to incorrect shapes, rather than rebuiling them to be the right shape.

Consider two uses for EM:

  • Radar style sensing (which requires tremendous dynamic range)
  • Communication (which requires fine tuning and allocation of bandwidth)

If we were to evolve such capabilities in one of the creatures we dream up, what would have to be fundamentally different than today's mechanical devices.

Particular features of today's devices that I think would cause a challenge:

  • Precise clocks. For things like wifi to work, a clock needs to have under 20ppm of error (I think that number is a jitter number, but it might have been a bias number). The demands of radar are often even higher. The jitter requirements on modern pulse-doppler radars are brutal!
  • Highly linear RF-frequency amplifies, needed to modulate or demodulate a signal.
  • Demanding antenna geometry (which may need to be identical across multiple individuals)
  • Dynamic range (we have radars today that output megawatts, and listen to echos in the femtowatt range!)
  • Privacy (hard unless you rely entirely on digital communications)
  • Lack of subtlety (our radios have no concept a. la tone of voice or body language)

Edit: I am particularly interested in the use of lower frequencies, such as microwaves and radio waves, where the wave mechanics force a macroscopic antenna.

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    $\begingroup$ Eyes are EM receivers. We also emit quite a bit in the low end of the IR range. In terms of emitting EMR for information purposes, there are a number of examples such as fireflies. $\endgroup$ – smithkm Nov 24 '14 at 2:37
  • $\begingroup$ You have an excellent point, smithkm. I have added a caveat to my question to address this. I am interested in the large wavelength EM transceivers, where wave mechanics dictate macroscopic antennas. I am less interested in the shorter wavelengths where traditional imaging becomes the easiest approach and microscopic antennas, such as molecules, become valid resonators. $\endgroup$ – Cort Ammon Nov 24 '14 at 5:26
  • $\begingroup$ Some hints may be found from electric fish $\endgroup$ – mouviciel Nov 25 '14 at 10:19
  • $\begingroup$ Precision clock? The only reason that we "need" them for radio bandwidth has been divided by FDMA by centralized architecture/policy. Given most tech uses FDMA, poor clocking would interfere with other systems. Biological system would likely be adaptive. $\endgroup$ – Aron Jan 7 '15 at 10:55
  • $\begingroup$ Dynamic range? At present the dynamic range of even the best HiFi system/Laser Display systems, are truly pathetic compared to the dynamic sensing range of the ear and eye respectively. $\endgroup$ – Aron Jan 7 '15 at 10:57
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The primary difference between a manufactured and an evolved EM transceiver system would be organisation. The manufactured system would be arranged logically because that is the way that its designers think about it. However, an evolved system would likely have components all jumbled together with surprising effects.

Evolved systems have proven to be more efficient and effective than most of the things we manufacture to do the same jobs today, though there are exceptions. Should any of the features mentioned in the question be important, I have no doubt that they could evolve.

One feature that I believe would be different between a manufactured and an evolved EM system would be multiplexing - an evolved EM system would be more likely to use broad swathes of the EM spectrum rather than our narrow-band manufactured systems. This would confer its own set of advantages.

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  • $\begingroup$ Good call on the broadband approach! I'd had AM, FM, and QAM in mind when I wrote this, but you're right that there's no reason evolution would limit themselves in such ways. $\endgroup$ – Cort Ammon Nov 24 '14 at 0:20
  • $\begingroup$ @CortAmmon QAM? Seriously? Just with our ears we have CDMA (we can ignore noise over human speech) & SDMA (we can resolve the direction of a speaker). Our brains are working at 4G style tech level. $\endgroup$ – Aron Jan 7 '15 at 10:50

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